A jellyfish is a soft-bodied, free-swimming marine animal with a gelatinous umbrella-shaped bell and trailing tentacles, typically transparent or bluish in color. Jellyfish are found in every ocean, from the surface to the deep sea. Some jellyfish are also capable of living in freshwater.
Jellyfish have been on Earth for at least 500 million years, and possibly even longer. They are among the oldest multi-organ animal groups on the planet. Jellyfish are thought to have evolved from a group of colonial organisms called comb jellies.
Jellyfish are not fish, but rather are classified as invertebrates, meaning they lack a backbone. However, they are still members of the animal kingdom. Jellyfish are made up of about 95% water. They average about 2% solid matter, which contains their digestive organs, nerves, and a simple muscle layer.
The bell-shaped body of a jellyfish is called the umbrella, or exumbrella. The umbrella is surrounded by a thin, transparent membrane called the epidermis. The epidermis is supported by eight radial canals, which extend from the margin of the umbrella to the center.
The umbrella contains the jellyfish's mouth, which is also its anus. Jellyfish do not have a brain or centralized nervous system. Instead, they have a network of nerves, called a nerve net, located in the epidermis. This nerve net allows the jellyfish to sense stimuli, such as the touch of a prey animal, and respond accordingly.
Jellyfish have two main types of tentacles: feeding tentacles and stinging tentacles. Feeding tentacles are used to capture prey and bring it to the mouth. Stinging tentacles are used to defend the jellyfish from predators and to capture prey.
Jellyfish use a variety of methods to capture prey. Some jellyfish simply wait for prey to swim into their mouth. Others actively pursue prey. Still others use their stinging tentacles to paralyze prey so that it can be more easily consumed.
Jellyfish are mostly passive predators, meaning they do not actively seek out prey. However, some species of jellyfish are known to be aggressive and will attack other animals, even humans, if they feel threatened.
Jellyfish are carnivores, meaning they eat other animals. Their diet consists mainly of small fish, crustaceans, and other invertebrates. Jellyfish use their tentacles to sting and paralyze their prey. They then bring the prey to their mouth, where it is pulled inside and digested.
Jellyfish are capable of reproducing both sexually and asexually. In sexual reproduction, male and female jellyfish release sperm and eggs into the water, where fertilization occurs. The fertilized eggs develop into larval stages, which eventually settle to the bottom and metamorphose into adult jellyfish.
Asexual reproduction occurs when a jellyfish splits into two or more parts, each of which grows into a new jellyfish. This process, called fragmentation, is common among many species of jellyfish.
Jellyfish are found in all oceans of the world, from the surface to the deep sea. They are also found in some freshwater lakes and rivers. Jellyfish are most common in warm, tropical waters.
Jellyfish are an important part of the marine food web. They are a food source for many animals, including fish, turtles, and seabirds. Jellyfish are also known to play an important role in controlling the populations of other animals, such as zooplankton.
Jellyfish are a fascinating and unique group of animals. They have been on Earth for millions of years and are found in every ocean. Jellyfish are beautiful, but also dangerous creatures. They are an important part of the marine food web and play a crucial role in controlling the populations of other animals.
Jellyfish: From Natural Wonders to Dinner Plate
When people think about Jellyfish, images of vibrant, delicate creatures flowing through the ocean come to mind. However, many don’t realize that these ethereal creatures can end up as dinner. From capture to plate, let’s discover the physics, biology, and engineering involved in getting Jellyfish from ocean to dinner table.
Jellyfish Capture: Harvesting in an Aquaculture Farm
Jellyfish are not typically in abundance in the wild, which makes them rare treats. To meet the increasing demand, Jellyfish are farmed through aquaculture. Aquaculture is the practice of farming fish, shellfish, plants, algae, and other aquatic organisms for human consumption.
In a typical Jellyfish aquaculture system, the Jellyfish are kept in a large pond with no in-flow or out-flow. A set amount of salinated water is added to the system each hour to replace what is lost from evaporation. The ponds are chosen due to enough sunlight to support algal photosynthesis, while also being shallow enough to limit the growth of predators.
The specific type of Jellyfish farming depends on the species being farmed. However, generally, natural filters are intentionally omitted, allowing water flow to carry food to the rearing tanks without evoking aggressive hunting behavior of the Jellyfish, which could damage them. The tanks can also be dimly lit to trigger nighttime hunting behavior, encouraging the Jellyfish to feed during the day where they are more easily harvested.
Infection Control and Selection
One key challenge with aquaculture, especially for Jellyfish, is infection prevention and control. Jellies suffer from a whole host of microbial diseases, meaning microbial control of their environment and pathogen detection are critical for both farming and health standards for eating Jellyfish.
To prevent infection of other organisms, many farms use ultraviolet light or ozone treated water. Ultraviolet light breaks down organic molecules, including bacteria, making it an effective disinfectant. Ozone, another form of oxygen, is a strong oxidizing agent, meaning it kills bacteria and other microorganisms by destroying their cell walls. By combining both of these disinfectants, farms can reduce the spread of disease and overall mortality rate.
When it comes to selecting the right Jellyfish to go to market, the traditional approach is visually inspecting the Jellyfish, one at a time, to check for deformities and imperfections. However, with the latest technological advancements, farmers have been utilizing the power of image processing analysis to reduce inspection times and improve accuracy. By using cameras and specialized software, farmers can quickly identify the most worthy crop of Jellyfish, streamlining the process significantly.
Harvesting and Processing
The next step in the ultimate journey of a Jellyfish is harvesting and preventing spoilage. During harvesting, harvesting poles are set into the Jellyfish tank, gathering the Jellies by their bell and allowing for a higher capture rate over hand picking.
During the harvesting process, determining which Jellyfish is good for human consumption is critical. The Jellyfish is assessed based on size, weight, color, and primary characteristics. The best Jellies are then selected from the catch and frozen or pickled in brine. Other Jellyfish, such as the moon jellyfish, can be freeze-dried after being caught, adding structure and allowing them to be stored and transported for longer periods of time.
The type of processing greatly depends on the culinary use for the Jellyfish. For example, if the Jellyfish is to be served raw, it may be bottled and vacuum sealed to preserve its freshness. If it is to be served cooked, either frozen or pickled, then the Jellyfish is dusted with wheat flour and parboiled to reduce its acidity and bitterness. Afterwards, the Jellyfish is rinsed to remove any residual flour.
In both instances, the processed Jellyfish is then stored in a cold chamber, slowing its decomposition until it is ready to be shipped.
Shipping: Traveling in Style
The last leg of the journey is transporting the caught or processed Jellyfish from the farming site or processing plant to retailers. Depending on how far the retailers are from the source, the Jellyfish will be transported in chilled containers. This not only keeps the Jellyfish fresh and reduces spoilage, but also ensures that their flavor isn’t affected by long-term exposure to heat.
The transportation of frozen and pickled Jellyfish is largely container based. Frozen Jellyfish are shipped in special, insulated containers containing several gel packs. Gel packs are used to maintain the temperature inside the containers, keeping the Jellyfish close to the freezing point (0°C or 32°F). This cool temperature prevents the Jellyfish from losing its cell wall integrity and taste, giving it its distinctive texture and flavor.
Pickled Jellyfish need slightly more specialized transport, as they are slightly more complex than their frozen counterparts. To ensure the security of pickled Jellyfish during transportation, the containers must be equipped with wet burlap packing and contain a hypochlorite solution that covers the bottom of the container, allowing the Jellyfish to remain submerged in the pickling liquid.
From the Aquaculture Farm to the Dinner Table
After traveling from faraway locations, from aquaculture farms to processing plants and eventually retailers, Jellyfish finally make their way to the dinner table.
In most cases, the Jellyfish is eaten raw as sashimi with a combination of wasabi, soy sauce, and horseradish. The combination of the soft texture and distinct taste of the Jellyfish adds a very different flavor to the dish. Jellyfish can also be served cooked in a variety of dishes, such as salads, tempura, and stir-fries.
The longer shelf life of frozen and pickled Jellyfish has led to increased consumption, bringing the maritime delicacies to culinary heights. Not only are Jellyfish incredibly nutritious, but they also offer immense benefits to wild populations as an ecologically sustainable seafood.
Jellyfish—From Ocean to Table
From oceans to aquaculture ponds, from capture to processing facilities, Jellyfish make an incredible journey from sea to plate. As we’ve seen in this article, bringing Jellyfish from natural wonders to dinner table involves incredible feats of physics, biology, and engineering.
Whether it’s raw or cooked, the unique texture and flavor of Jellyfish makes it a culinary delight for seafood lovers. Because of a longer shelf life, people are now able to enjoy the delicacies of Jellyfish beyond the waters of their natural homes, celebrating these magical creatures in many countries.
Vitamin A | 0.002 mg | |
Vitamin E | 0.02 mg | |
Vitamin K | 0.1 ug | |
Vitamin B1 | 0.01 mg | |
Vitamin B2 | 0.01 mg | |
Vitamin B3 | 0.2 mg | |
Vitamin B4 | 0.095 grams | |
Vitamin B6 | 0.01 mg | |
Vitamin B9 | 0.001 mg | |
Vitamin B12 | 0.02 ug |
Calcium | 0.002 grams |
Daily Value 1.3 g
|
Iron | 0.00227 grams |
Daily Value 0.018 g
|
Magnesium | 0.002 grams |
Daily Value 0.4 g
|
Phosphorus | 0.02 grams |
Daily Value 1.25 g
|
Potassium | 0.003 grams |
Daily Value 4.7 g
|
Sodium | 9.69 grams |
Daily Value 2.3 g
|
Zinc | 0.42 mg |
Daily Value 0.011 g
|
Copper | 0.14 mg |
Daily Value 0.9 mg
|
Selenium | 0.0422 mg |
Daily Value 0.055 mg
|
Total Sugars | 0 ug |
per 100g
|
Myristic acid (14:0) | 0.02 grams |
|
Palmitic acid (16:0) | 0.19 grams |
|
Stearic acid (18:0) | 0.06 grams |
|
Total Saturated fatty acids: | 0.27 g | |
Erucic acid (22:1) | 0.01 grams |
|
Oleic acid (18:1) | 0.13 grams |
|
Palmitoleic acid (16:1) | 0.03 grams |
|
Gadoleic acid (20:1) | 0.03 grams |
|
Total Monounsaturated fatty acids: | 0.2 g | |
Omega-3 Timnodonic acid (20:5) | 0.01 grams |
|
Omega-3 Clupanodonic acid (22:5) | 0.02 grams |
|
Linoleic acid (18:2) | 0.01 grams |
|
Total Polyunsaturated fatty acids: | 0.04 g | |
Cholesterol | 0.01 grams |
|
Total Sterols: | 0.01 g |